Java tutorial
package org.jsoup.nodes; import org.jsoup.Connection; import org.jsoup.Jsoup; import org.jsoup.helper.HttpConnection; import org.jsoup.helper.Validate; import org.jsoup.parser.Tag; import org.jsoup.select.Elements; import java.util.ArrayList; import java.util.List; /** * A HTML Form Element provides ready access to the form fields/controls that are associated with it. It also allows a * form to easily be submitted. */ public class FormElement extends Element { private final Elements elements = new Elements(); /** * Create a new, standalone form element. * * @param tag tag of this element * @param baseUri the base URI * @param attributes initial attributes */ public FormElement(Tag tag, String baseUri, Attributes attributes) { super(tag, baseUri, attributes); } /** * Get the list of form control elements associated with this form. * @return form controls associated with this element. */ public Elements elements() { return elements; } /** * Add a form control element to this form. * @param element form control to add * @return this form element, for chaining */ public FormElement addElement(Element element) { elements.add(element); return this; } @Override protected void removeChild(Node out) { super.removeChild(out); elements.remove(out); } /** * Prepare to submit this form. A Connection object is created with the request set up from the form values. You * can then set up other options (like user-agent, timeout, cookies), then execute it. * @return a connection prepared from the values of this form. * @throws IllegalArgumentException if the form's absolute action URL cannot be determined. Make sure you pass the * document's base URI when parsing. */ public Connection submit() { String action = hasAttr("action") ? absUrl("action") : baseUri(); Validate.notEmpty(action, "Could not determine a form action URL for submit. Ensure you set a base URI when parsing."); Connection.Method method = attr("method").toUpperCase().equals("POST") ? Connection.Method.POST : Connection.Method.GET; return Jsoup.connect(action).data(formData()).method(method); } /** * Get the data that this form submits. The returned list is a copy of the data, and changes to the contents of the * list will not be reflected in the DOM. * @return a list of key vals */ public List<Connection.KeyVal> formData() { ArrayList<Connection.KeyVal> data = new ArrayList<>(); // iterate the form control elements and accumulate their values for (Element el : elements) { if (!el.tag().isFormSubmittable()) continue; // contents are form listable, superset of submitable if (el.hasAttr("disabled")) continue; // skip disabled form inputs String name = el.attr("name"); if (name.length() == 0) continue; String type = el.attr("type"); if ("select".equals(el.tagName())) { Elements options = el.select("option[selected]"); boolean set = false; for (Element option : options) { data.add(HttpConnection.KeyVal.create(name, option.val())); set = true; } if (!set) { Element option = el.select("option").first(); if (option != null) data.add(HttpConnection.KeyVal.create(name, option.val())); } } else if ("checkbox".equalsIgnoreCase(type) || "radio".equalsIgnoreCase(type)) { // only add checkbox or radio if they have the checked attribute if (el.hasAttr("checked")) { final String val = el.val().length() > 0 ? el.val() : "on"; data.add(HttpConnection.KeyVal.create(name, val)); } } else { data.add(HttpConnection.KeyVal.create(name, el.val())); } } return data; } }